JSFiddle - React, Tailwind, and code Playground

by Igor Cuckovic

JavaScript

// http://stackoverflow.com/questions/4109836/help-with-spiral-matrix

var svg = d3.select("body").append("svg").attr({
    "width": "100%",
    "height": "100%",
    "fill": "#3E3E40"
});

svg.append("rect").attr({
    "x": 0,
    "y": 0,
    "width": "100%",
    "height": "100%",
    "fill": "#3E3E40"
});


svg.append("rect").attr({
    "x": 100,
    "y": 100,
    "width": 44,
    "height": 44,
    "rx": 2,
    "ry": 2,
    "fill": "none",
    "stroke": "#ffffff"
});